This invention relates to a solid material packing method in which a solid material such as ham is packed in a film bag, and to a machine for practicing the method.
In a conventional solid material packing method, a number of film bags, which have been formed according to the size of the solid materials to be packed, are manually picked up one after another and manually opened, and the solid materials are manually packed in the film bags. However, this conventional method is disadvantageous in that, since the packing work is carried out manually, the work efficiency is low especially when large rectangular solid materials are packed.
Furthermore, there is also known a solid material packing method in which a number of film bags are stuck to a piece of adhesive tape in such a manner that they overlap one another, and the film bags are supplied one after another each time a packing cycle is completed, with a packing cycle comprising the opening of a film bag, putting a solid material into the film bag and removing the film bag, so that solid materials are continuously packed. However, this latter method is still disadvantageous in that both the forming of the assembly of film bags stuck to the piece of adhesive tape and the setting of the assembly of film bags are troublesome.
There are also known packing machines in which a vacuum operated suction and retaining head is employed to remove the bags from a stack one at a time, but this is still disadvantageous in that it is difficult to positively pick up the thin plastic bags, and the bags are also sometimes wrinkled.
Solid material packing machines also differ in their particular means for supplying the material into the bag. In the case where a relatively thick, cylindrical material is to be packed into a bag, it is common to place a sufficiently opened bag in front of the front end portion of a cylindrical chute, and the material is then delivered into the bag through the chute. However, in such a system, it is necessary to provide an intricate mechanism for opening the mouth of the bag and for placing the opened bag in front of the chute. When the size of the materials to be packed is changed, it is difficult to quickly respond to this change.